JP7562983B2 - Method for producing porous hollow fiber membrane - Google Patents
Method for producing porous hollow fiber membrane Download PDFInfo
- Publication number
- JP7562983B2 JP7562983B2 JP2020073459A JP2020073459A JP7562983B2 JP 7562983 B2 JP7562983 B2 JP 7562983B2 JP 2020073459 A JP2020073459 A JP 2020073459A JP 2020073459 A JP2020073459 A JP 2020073459A JP 7562983 B2 JP7562983 B2 JP 7562983B2
- Authority
- JP
- Japan
- Prior art keywords
- hollow fiber
- fiber membrane
- heat
- relaxing
- porous hollow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000012510 hollow fiber Substances 0.000 title claims description 151
- 239000012528 membrane Substances 0.000 title claims description 134
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- 238000011282 treatment Methods 0.000 claims description 44
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 26
- 229920005672 polyolefin resin Polymers 0.000 claims description 23
- 238000000034 method Methods 0.000 claims description 17
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 238000009987 spinning Methods 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 6
- 238000002844 melting Methods 0.000 claims description 5
- 230000008018 melting Effects 0.000 claims description 5
- 239000002994 raw material Substances 0.000 claims description 5
- 238000002074 melt spinning Methods 0.000 claims description 4
- 238000000691 measurement method Methods 0.000 claims description 3
- -1 polyethylene Polymers 0.000 description 10
- 239000011148 porous material Substances 0.000 description 9
- 239000004698 Polyethylene Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 229920000573 polyethylene Polymers 0.000 description 7
- 238000000137 annealing Methods 0.000 description 6
- 230000015556 catabolic process Effects 0.000 description 4
- 238000006731 degradation reaction Methods 0.000 description 4
- 239000000835 fiber Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 239000004743 Polypropylene Substances 0.000 description 3
- 230000009477 glass transition Effects 0.000 description 3
- 229920001155 polypropylene Polymers 0.000 description 3
- 238000005406 washing Methods 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000010840 domestic wastewater Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000010842 industrial wastewater Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- WSSSPWUEQFSQQG-UHFFFAOYSA-N 4-methyl-1-pentene Chemical compound CC(C)CC=C WSSSPWUEQFSQQG-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 229920006026 co-polymeric resin Polymers 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 125000001153 fluoro group Chemical group F* 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 239000010954 inorganic particle Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005374 membrane filtration Methods 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 238000004382 potting Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Images
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Artificial Filaments (AREA)
Description
本発明は、多孔質中空糸膜及びその製造方法、並びに前記多孔質中空糸膜を有する中空糸膜エレメントに関する。 The present invention relates to a porous hollow fiber membrane, a method for producing the same, and a hollow fiber membrane element having the porous hollow fiber membrane.
例えば、生活排水や工場排水等の浄化処理には、多孔質中空糸膜が好適に用いられる。多孔質中空糸膜は、複数の多孔質中空糸膜を一方向に引き揃えて一体的に保持した中空糸膜エレメントの形態で用いられることが多い。 For example, porous hollow fiber membranes are suitable for use in the purification treatment of domestic and industrial wastewater. Porous hollow fiber membranes are often used in the form of hollow fiber membrane elements, in which multiple porous hollow fiber membranes are aligned in one direction and held together as a unit.
多孔質中空糸膜を用いた水処理では、被処理水を貯留した処理槽に中空糸膜エレメントを浸漬し、例えば、多孔質中空糸膜の外方から内方へ被処理水を吸引することによって、汚濁物質を多孔質中空糸膜の外面で捕捉する。
また、汚濁物質によって多孔質中空糸膜が目詰まりするのを防止するために、必要に応じて、中空糸膜エレメントを洗浄する。
ここで、例えば、特許文献１には、排水処理の処理槽から中空糸膜エレメントを引き上げて洗浄する方法が記載されている。
In water treatment using a porous hollow fiber membrane, a hollow fiber membrane element is immersed in a treatment tank containing the water to be treated, and the water to be treated is sucked from the outside to the inside of the porous hollow fiber membrane, for example, to capture pollutants on the outer surface of the porous hollow fiber membrane.
In order to prevent the porous hollow fiber membranes from becoming clogged with contaminants, the hollow fiber membrane elements are washed as necessary.
For example, Patent Document 1 describes a method for lifting a hollow fiber membrane element from a treatment tank of a wastewater treatment system and washing it.
中空糸膜エレメントを処理槽から引き上げて洗浄し、再び処理槽に浸漬して使用する操作を繰り返すと、性能が低下したり、多孔質中空糸膜の糸切れが生じたりするため、その場合には新品に交換する必要がある。
本発明者の知見によれば、中空糸膜エレメントを処理槽から引き上げて空気中で洗浄操作を行うと、多孔質中空糸膜が乾燥して収縮する場合があり、多孔質中空糸膜の収縮が大きいと性能低下や糸切れが生じやすい。
本発明は、中空糸膜エレメントの製品寿命を延ばすことができる多孔質中空糸膜及びその製造方法、並びに前記多孔質中空糸膜を有する中空糸膜エレメントの提供を目的とする。
If the hollow fiber membrane element is repeatedly removed from the treatment tank, washed, and then immersed in the treatment tank again for use, its performance may deteriorate and the porous hollow fiber membrane may break, making it necessary to replace it with a new one.
According to the inventors' findings, when a hollow fiber membrane element is removed from a treatment tank and subjected to a cleaning operation in air, the porous hollow fiber membrane may dry out and shrink, and if the porous hollow fiber membrane shrinks significantly, performance degradation and fiber breakage are likely to occur.
An object of the present invention is to provide a porous hollow fiber membrane capable of extending the product life of a hollow fiber membrane element, a method for producing the same, and a hollow fiber membrane element having the porous hollow fiber membrane.
［１］ ポリオレフィン系樹脂からなり、下記の測定方法で得られる収縮率が３％以下である、多孔質中空糸膜。
測定方法：長さ４００ｍｍの多孔質中空糸膜を、エタノールに１０分間浸漬した後、純水に１０分間浸漬し、６０℃の雰囲気中で３０分間乾燥した後、室温で５分間冷却する浸漬処理を行い、処理後の前記多孔質中空糸膜の長さＬ１（単位：ｍｍ）を測定し、下記式（Ｉ）により収縮率（単位：％）を算出する。
収縮率＝（４００－Ｌ１）／４００×１００ ・・・（Ｉ）
［２］ 前記ポリオレフィン系樹脂のガラス転移温度が４０℃以下である、［１］の多孔質中空糸膜。
［３］ 前記ポリオレフィン系樹脂がポリエチレンを含む、［１］又は［２］の多孔質中空糸膜。
［４］ ［１］～［３］のいずれかの多孔質中空糸膜の複数本と、前記複数本の多孔質中空糸膜の両端に接続された集水管とを有する、中空糸膜エレメント。
［５］ 請求項１～３のいずれか一項に記載の多孔質中空糸膜を製造する方法であって、前記ポリオレフィン系樹脂を含む原料を溶融紡糸して中空糸を得る紡糸工程と、前記中空糸を延伸して中空糸膜を得る延伸工程と、前記中空糸膜を熱緩和処理する熱緩和工程とを有する、多孔質中空糸膜の製造方法。
[1] A porous hollow fiber membrane made of a polyolefin resin and having a shrinkage rate of 3% or less as measured by the following method.
Measurement method: A porous hollow fiber membrane having a length of 400 mm is immersed in ethanol for 10 minutes, then immersed in pure water for 10 minutes, dried in an atmosphere at 60°C for 30 minutes, and then cooled at room temperature for 5 minutes. The length L1 (unit: mm) of the porous hollow fiber membrane after the treatment is measured, and the shrinkage rate (unit: %) is calculated by the following formula (I).
Shrinkage rate = (400 - L1) / 400 x 100 ... (I)
[2] The porous hollow fiber membrane according to [1], wherein the polyolefin resin has a glass transition temperature of 40° C. or lower.
[3] The porous hollow fiber membrane according to [1] or [2], wherein the polyolefin resin contains polyethylene.
[4] A hollow fiber membrane element comprising a plurality of the porous hollow fiber membranes according to any one of [1] to [3] and water collection pipes connected to both ends of the plurality of porous hollow fiber membranes.
[5] A method for producing the porous hollow fiber membrane according to any one of claims 1 to 3, comprising a spinning step of melt-spinning a raw material containing the polyolefin resin to obtain a hollow fiber, a stretching step of stretching the hollow fiber to obtain a hollow fiber membrane, and a heat-relaxing step of heat-relaxing the hollow fiber membrane.
本発明の多孔質中空糸膜は、水に浸漬した後に乾燥したときの収縮率が小さいため、洗浄に伴う性能低下や糸切れが生じ難い。
本発明の中空糸膜エレメントは、水に浸漬した後に乾燥したときの多孔質中空糸膜の収縮率が小さいため、洗浄に伴う性能低下や糸切れが生じ難い。
本発明の多孔質中空糸膜の製造方法によれば、水に浸漬した後に乾燥したときの収縮率が小さい多孔質中空糸膜が得られる。
The porous hollow fiber membrane of the present invention has a small shrinkage rate when immersed in water and then dried, and is therefore less susceptible to performance degradation and fiber breakage due to washing.
The hollow fiber membrane element of the present invention has a small shrinkage rate of the porous hollow fiber membrane when immersed in water and then dried, and therefore is less susceptible to performance degradation and fiber breakage due to washing.
According to the method for producing a porous hollow fiber membrane of the present invention, a porous hollow fiber membrane having a small shrinkage rate when immersed in water and then dried can be obtained.
＜多孔質中空糸膜＞
本実施形態の多孔質中空糸膜はポリオレフィン系樹脂からなる。
本明細書において、ポリオレフィン系樹脂とは、アルケン（水素原子の一部がフッ素原子に置換されていてもよい。）に基づく単位の１種以上からなる重合体である。ここで、ポリオレフィン系樹脂の例としては、ポリエチレン、ポリプロピレン、ポリ－４メチルペンテン－１、ポリフッ化ビニリデン、ポリオレフィン系共重合樹脂などが挙げられる。多孔質中空糸膜を構成するポリオレフィン系樹脂は１種でもよく、２種以上の混合物でもよい。また、ポリオレフィン系樹脂以外の樹脂、有機材料、無機材料との混合物でもよい。
液体濾過時に膜材からの溶出を抑制できる溶融紡糸多孔化の容易性の点で、多孔質中空糸膜を構成するポリオレフィン系樹脂が、ポリエチレン又はポリプロピレンを含むことが好ましく、特にポリエチレンを含むことがより好ましい。
<Porous hollow fiber membrane>
The porous hollow fiber membrane of this embodiment is made of a polyolefin resin.
In this specification, a polyolefin resin is a polymer consisting of one or more types of units based on an alkene (wherein some of the hydrogen atoms may be substituted with fluorine atoms). Examples of polyolefin resins include polyethylene, polypropylene, poly-4-methylpentene-1, polyvinylidene fluoride, and polyolefin copolymer resins. The polyolefin resin constituting the porous hollow fiber membrane may be one type or a mixture of two or more types. In addition, it may be a mixture with a resin other than the polyolefin resin, an organic material, or an inorganic material.
From the viewpoint of ease of melt-spinning porosity that can suppress elution from the membrane material during liquid filtration, it is preferable that the polyolefin resin constituting the porous hollow fiber membrane contains polyethylene or polypropylene, and it is more preferable that it contains polyethylene.
一般的に水処理における膜濾過温度は４０℃以下であることが多い。多孔質中空糸膜の使用温度がガラス転移温度よりも高いと、多孔質中空糸膜を構成しているポリマー鎖が動けるため、残存応力が生じやすい。残留応力は多孔質中空糸膜の収縮の原因となる。したがって、多孔質中空糸膜を構成するポリオレフィン系樹脂のガラス転移温度（以下、Ｔｇともいう。）が４０℃以下であると、本発明を適用することによる効果が得られやすい。
Ｔｇが４０℃以下であるポリオレフィン系樹脂の具体例としては、ポリエチレン（Ｔｇ：－１２５℃）、ポリプロピレン（Ｔｇ：０℃）が挙げられる。
多孔質中空糸膜を構成するポリオレフィン系樹脂が２種以上である場合、それぞれのＴｇが４０℃以下であることが好ましい。
Generally, the membrane filtration temperature in water treatment is often 40°C or less. If the use temperature of the porous hollow fiber membrane is higher than the glass transition temperature, the polymer chains constituting the porous hollow fiber membrane are mobile, so residual stress is likely to occur. The residual stress causes the porous hollow fiber membrane to shrink. Therefore, if the glass transition temperature (hereinafter also referred to as Tg) of the polyolefin resin constituting the porous hollow fiber membrane is 40°C or less, the effect of applying the present invention is easily obtained.
Specific examples of polyolefin resins having a Tg of 40° C. or less include polyethylene (Tg: −125° C.) and polypropylene (Tg: 0° C.).
When the porous hollow fiber membrane is composed of two or more types of polyolefin resins, it is preferable that each of them has a Tg of 40° C. or less.
本実施形態の多孔質中空糸膜は、前記ポリオレフィン系樹脂からなる中空糸膜の表面（外側表面、内側表面及び孔内部の表面）の少なくとも一部にコーティング層を有してもよい。例えば、多孔質中空糸膜の表面に、親水性樹脂、界面活性剤、無機粒子等が存在してもよい。 The porous hollow fiber membrane of this embodiment may have a coating layer on at least a portion of the surface (outer surface, inner surface, and surface inside the pores) of the hollow fiber membrane made of the polyolefin resin. For example, a hydrophilic resin, a surfactant, inorganic particles, etc. may be present on the surface of the porous hollow fiber membrane.
多孔質中空糸膜の平均孔径は特に限定されない。例えば０．０２～０．５μｍが好ましい。
本明細書において、多孔質中空糸膜の平均孔径は、ＪＩＳ Ｋ ３８３２に準拠した細孔径分布測定装置を用いて得られた細孔径分布におけるピーク値である。
The average pore size of the porous hollow fiber membrane is not particularly limited, and is preferably 0.02 to 0.5 μm, for example.
In this specification, the average pore size of the porous hollow fiber membrane is the peak value in the pore size distribution obtained using a pore size distribution measuring device in accordance with JIS K 3832.
多孔質中空糸膜の外径および内径は特に限定されない。使用用途やエレメント形状などにより任意に選ぶことができる。一般的には外径３００～１０００μｍ程度の範囲で選ばれることが多い。 The outer and inner diameters of the porous hollow fiber membrane are not particularly limited. They can be selected as desired depending on the intended use and element shape. In general, the outer diameter is often selected in the range of about 300 to 1000 μm.
本実施形態の多孔質中空糸膜は、下記の測定方法で得られる収縮率が３％以下である。
前記収縮率が低いほど寸法安定性に優れる。前記収縮率は２％以下が好ましく、１．５％以下がより好ましい。
The porous hollow fiber membrane of the present embodiment has a shrinkage rate of 3% or less, as measured by the following method.
The lower the shrinkage rate, the more excellent the dimensional stability. The shrinkage rate is preferably 2% or less, and more preferably 1.5% or less.
収縮率の測定方法：長さ４００ｍｍの多孔質中空糸膜を、エタノールに１０分間浸漬した後、純水に１０分間浸漬し、６０℃の雰囲気中で３０分間乾燥した後、室温で５分間冷却する浸漬処理を行い、処理後の前記多孔質中空糸膜の長さＬ１（単位：ｍｍ）を測定し、下記式（Ｉ）により収縮率（単位：％）を算出する。
収縮率＝（４００－Ｌ１）／４００×１００ ・・・（Ｉ）
Method for measuring shrinkage rate: A porous hollow fiber membrane having a length of 400 mm is immersed in ethanol for 10 minutes, then immersed in pure water for 10 minutes, dried in an atmosphere at 60°C for 30 minutes, and then cooled at room temperature for 5 minutes. The length L1 (unit: mm) of the porous hollow fiber membrane after the treatment is measured, and the shrinkage rate (unit: %) is calculated by the following formula (I).
Shrinkage rate = (400 - L1) / 400 x 100 ... (I)
前記収縮率は、具体的に以下の方法で測定する。
（１）まず、多孔質中空糸膜（１フィラメント）を５００ｍｍの長さに切断して試験体とする。試験体の一端を固定し、他端を自重で垂下させる。他端の先端に５０ｍｇ／ｄｔｅｘの荷重をかけた状態で、両端を除く長さ４００ｍｍの部分（被測定部分）に印をつける。
（２）次に、浸漬処理を行う。すなわち、試験体をエタノール（室温）に１０分間浸漬した後、取り出し、続いて純水（室温）に１０分間浸漬して取り出す。試験体の一端を固定し他端を自重で垂下させた状態で、雰囲気温度６０℃の乾燥機内で３０分間乾燥させた後、室温で５分間冷却する。
（３）次いで、前記（１）と同様に試験体の他端の先端に５０ｍｇ／ｄｔｅｘの荷重をかけた状態で、前記（１）で印をつけた前記被測定部分の長さＬ１（単位：ｍｍ）を測定する。
（４）前記式（Ｉ）により収縮率を算出する。
なお、本明細書において「室温」とは、特に断りの無い限り２３℃±２℃の範囲内の温度を意味する。
The shrinkage rate is specifically measured by the following method.
(1) First, a porous hollow fiber membrane (one filament) is cut to a length of 500 mm to prepare a test specimen. One end of the test specimen is fixed, and the other end is allowed to hang down under its own weight. With a load of 50 mg/dtex applied to the tip of the other end, a mark is made on a 400 mm long portion (measurement portion) excluding both ends.
(2) Next, an immersion treatment is performed. That is, the test specimen is immersed in ethanol (room temperature) for 10 minutes, then removed, and subsequently immersed in pure water (room temperature) for 10 minutes and then removed. With one end of the test specimen fixed and the other end hanging down under its own weight, it is dried in a dryer at an atmospheric temperature of 60° C. for 30 minutes, and then cooled at room temperature for 5 minutes.
(3) Next, in the same manner as in (1) above, a load of 50 mg/dtex is applied to the tip of the other end of the test specimen, and the length L1 (unit: mm) of the measurement portion marked in (1) above is measured.
(4) The shrinkage rate is calculated according to the above formula (I).
In this specification, "room temperature" means a temperature within the range of 23°C ± 2°C unless otherwise specified.
本実施形態の多孔質中空糸膜に、中空糸膜を補強するための支持体（例えば、編紐や組紐等の繊維状物）を設けてもよく、設けなくてもよい。本発明を適用することによる効果が優位に示される点で、支持体を含まない多孔質中空糸膜が好適である。 The porous hollow fiber membrane of this embodiment may or may not be provided with a support (e.g., a fibrous material such as a knitted cord or braided cord) to reinforce the hollow fiber membrane. A porous hollow fiber membrane that does not include a support is preferable because the effects of applying the present invention are more prominent.
＜多孔質中空糸膜の製造方法＞
本実施形態の多孔質中空糸膜は、ポリオレフィン系樹脂を含む原料を溶融紡糸して中空糸を得る紡糸工程と、前記中空糸を延伸して中空糸膜を得る延伸工程と、前記中空糸膜を熱緩和処理する熱緩和工程とを有する方法で製造される。紡糸工程と延伸工程との間に、任意の工程を設けてもよい。
延伸工程と熱緩和工程との間に任意の工程を設けてもよい。
熱緩和工程の後に、延伸を伴わない任意の工程を設けてもよい。
<Method for producing porous hollow fiber membrane>
The porous hollow fiber membrane of the present embodiment is produced by a method including a spinning step of melt-spinning a raw material containing a polyolefin resin to obtain a hollow fiber, a stretching step of stretching the hollow fiber to obtain a hollow fiber membrane, and a heat-relaxing step of heat-relaxing the hollow fiber membrane. An optional step may be provided between the spinning step and the stretching step.
An optional step may be provided between the stretching step and the heat-relaxing step.
After the heat-relaxing step, an optional step not involving stretching may be performed.
［紡糸工程～延伸工程］
紡糸工程から延伸工程までは公知の方法を用いることができる。
例えば、ポリオレフィン系樹脂を含む原料を溶融紡糸し、冷却固化して中空糸を得て、中空糸を延伸することによって、内面から外面にかけてスリット状の微細孔が相互につながった連通孔を有する多孔質中空糸膜を形成することができる。
例えば、特願２０１７－０８１７８３号公報の段落００３３～００４９に記載の方法等を用いることができる。
[Spinning process to drawing process]
From the spinning step to the drawing step, known methods can be used.
For example, a raw material containing a polyolefin resin is melt-spun, cooled and solidified to obtain hollow fibers, and the hollow fibers are stretched to form a porous hollow fiber membrane having interconnected slit-shaped micropores from the inner surface to the outer surface.
For example, the method described in paragraphs 0033 to 0049 of Japanese Patent Application No. 2017-081783 can be used.
延伸工程では、中空糸を搬送しながら加熱して延伸し、中空糸膜とする。
延伸時の雰囲気温度（延伸温度ｔ）は、中空糸を構成するポリオレフィン系樹脂のビカット軟化点以下であることが好ましい。延伸温度ｔがビカット軟化点以下であると、多孔質中空糸膜の孔径を拡大しやすい。延伸温度ｔがビカット軟化点を超えると孔が閉塞する場合がある。
In the stretching step, the hollow fibers are heated and stretched while being transported to form hollow fiber membranes.
The atmospheric temperature during stretching (stretching temperature t) is preferably equal to or lower than the Vicat softening point of the polyolefin resin constituting the hollow fiber. If the stretching temperature t is equal to or lower than the Vicat softening point, the pore size of the porous hollow fiber membrane is easily enlarged. If the stretching temperature t exceeds the Vicat softening point, the pores may be blocked.
紡糸工程の後、延伸工程に先立って、中空糸をアニール処理（定長熱処理）することが好ましい。
アニール処理では、中空糸を巻き取った状態で加熱することが好ましい。アニール処理を行う際の加熱温度（雰囲気温度）は、中空糸を構成するポリオレフィン系樹脂の融点以下とする。
例えばポリオレフィン系樹脂としてポリエチレンを用いる場合、雰囲気温度１０５～１３０℃、８～１６時間の条件で、中空糸を加熱することが好ましい。
After the spinning step, the hollow fibers are preferably subjected to an annealing treatment (fixed length heat treatment) prior to the drawing step.
In the annealing treatment, it is preferable to heat the hollow fiber in a wound state. The heating temperature (ambient temperature) during the annealing treatment is set to be equal to or lower than the melting point of the polyolefin resin constituting the hollow fiber.
For example, when polyethylene is used as the polyolefin resin, it is preferable to heat the hollow fibers at an atmospheric temperature of 105 to 130° C. for 8 to 16 hours.
アニール処理を行う場合、アニール処理の後、冷延伸を行ってから、前記延伸温度ｔで行う延伸（熱延伸）を行うことが好ましい。
冷延伸は、比較的低い温度下で膜の構造破壊を起きせ、ミクロなクラッキングを発生させる延伸である。冷延伸を行う際の雰囲気温度は、中空糸を構成するポリオレフィン系樹脂のビカット軟化点より２０℃以上低い温度（ビカット軟化点－２０℃以下）が好ましい。下限は０℃以上が好ましい。冷延伸の延伸倍率は１．２～１．８倍が好ましい。
アニール処理及び冷延伸を行う場合の延伸工程は、冷延伸に引き続いて熱延伸を行う２段延伸でもよく、冷延伸に引き続いて熱延伸を２段以上の多段に分割して行う多段延伸でもよい。
When annealing is performed, it is preferable to perform cold stretching after annealing, and then perform stretching at the stretching temperature t (hot stretching).
Cold stretching is a stretching method that breaks down the structure of the membrane at a relatively low temperature and generates micro-cracking. The atmospheric temperature during cold stretching is preferably at least 20°C lower than the Vicat softening point of the polyolefin resin constituting the hollow fiber (Vicat softening point -20°C or lower). The lower limit is preferably 0°C or higher. The stretching ratio in cold stretching is preferably 1.2 to 1.8 times.
The stretching process in the case where annealing and cold stretching are performed may be a two-stage stretching in which cold stretching is followed by hot stretching, or a multi-stage stretching in which cold stretching is followed by hot stretching divided into two or more stages.
中空糸に対する多孔質中空糸膜の総延伸倍率は、２～５倍が好ましい。総延伸倍率が２倍以上であると空孔率が高くなりやすく、５倍以下であると破断伸度が高くなりやすい。 The total stretch ratio of the porous hollow fiber membrane to the hollow fiber is preferably 2 to 5 times. If the total stretch ratio is 2 times or more, the porosity tends to be high, and if it is 5 times or less, the breaking elongation tends to be high.
［熱緩和工程］
熱緩和工程では、延伸工程で生じた残存応力を緩和できる温度で、中空糸膜を加熱（熱緩和処理）した後、冷却する。中空糸膜を搬送しながら加熱することが好ましい。送り出し速度より巻き取り速度を遅くして、中空糸膜を弛緩させた状態で加熱することが好ましい。
熱緩和処理における雰囲気温度（熱緩和温度Ｔ）は、中空糸膜を構成するポリオレフィン系樹脂の融点以下とする。熱緩和温度Ｔと融点との差は５～３５℃が好ましい。
熱緩和処理における、（１－巻き取り速度／送り出し速度）×１００で表される緩和率（単位：％）は０％以上であり、０～３５％が好ましく、１０～２０％がより好ましい。緩和率が上記範囲内であると製造の安定性と収縮率および膜性能を両立させる点で好ましい。
[Heat relaxation process]
In the heat-relaxing step, the hollow fiber membrane is heated (heat-relaxed) at a temperature at which the residual stress generated in the stretching step can be relaxed, and then cooled. It is preferable to heat the hollow fiber membrane while transporting it. It is preferable to heat the hollow fiber membrane in a relaxed state by making the winding speed slower than the delivery speed.
The atmospheric temperature in the heat-relaxing treatment (heat-relaxing temperature T) is set to be equal to or lower than the melting point of the polyolefin resin constituting the hollow fiber membrane. The difference between the heat-relaxing temperature T and the melting point is preferably 5 to 35°C.
In the heat-relaxing treatment, the relaxation rate (unit: %) expressed by (1-winding speed/delivering speed) x 100 is 0% or more, preferably 0 to 35%, and more preferably 10 to 20%. A relaxation rate within the above range is preferable in terms of achieving both production stability and shrinkage rate and film performance.
熱緩和工程において、熱緩和処理を複数回行ってもよい。
複数回の熱緩和処理の条件は同じであってもよく、異なってもよい。また、生産及び品質安定性の観点で、熱緩和処理は２回以上行うことが好ましい。
In the heat-relaxing step, the heat-relaxing treatment may be performed multiple times.
The conditions for the multiple heat-relaxing treatments may be the same or different, and from the viewpoints of production and quality stability, it is preferable to carry out the heat-relaxing treatment two or more times.
１回の熱緩和処理において、中空糸膜が熱緩和温度Ｔの雰囲気中に存在する時間（加熱時間）は５秒～１０分間が好ましく、１０秒～５分間がより好ましい。上記範囲内であると残存応力を十分低減できるとともに、生産性良く製造することができる。 In one heat relaxation treatment, the time (heating time) during which the hollow fiber membrane is in an atmosphere at the heat relaxation temperature T is preferably 5 seconds to 10 minutes, and more preferably 10 seconds to 5 minutes. If it is within the above range, the residual stress can be sufficiently reduced and the membrane can be produced with good productivity.
熱緩和工程における、熱緩和温度Ｔ、緩和率、加熱時間、及び熱緩和処理の回数のうちの１つ以上を変化させることで、多孔質中空糸膜の収縮率を調整することができる。
例えば、熱緩和温度Ｔを高めると収縮率が低下する傾向がある。熱緩和率を高めると収縮率が低下する傾向がある。加熱時間を長くすると収縮率が低下する傾向がある。熱緩和処理の回数を増やすと収縮率が低下する傾向がある。
In the heat-relaxing step, the shrinkage rate of the porous hollow fiber membrane can be adjusted by changing one or more of the heat-relaxing temperature T, the relaxation rate, the heating time, and the number of times of heat-relaxing treatment.
For example, increasing the heat relaxation temperature T tends to decrease the shrinkage rate. Increasing the heat relaxation rate tends to decrease the shrinkage rate. Increasing the heating time tends to decrease the shrinkage rate. Increasing the number of heat relaxation treatments tends to decrease the shrinkage rate.
［親水化工程］
必要に応じて、中空糸膜を親水化処理することにより、多孔質中空糸膜に親水性を付与することできる。親水化処理は公知の方法を用いることができる。
例えば、中空糸膜の表面（外側表面、内側表面及び孔内部の表面）の少なくとも一部を、親水性樹脂でコーティングする方法で親水化処理できる。具体的には、特許第３６２８４４６号公報の段落００２９に記載の方法等を用いることができる。
[Hydrophilication process]
If necessary, the hollow fiber membrane can be subjected to a hydrophilization treatment to impart hydrophilicity to the porous hollow fiber membrane. The hydrophilization treatment can be carried out by a known method.
For example, at least a part of the surface of the hollow fiber membrane (the outer surface, the inner surface, and the surface inside the pores) can be hydrophilized by coating with a hydrophilic resin. Specifically, the method described in paragraph 0029 of Japanese Patent No. 3628446 can be used.
親水化処理は、延伸工程の後かつ熱緩和工程の前に行ってもよく、延伸工程及び熱緩和工程の後に行ってもよく、熱緩和工程の途中で行ってもよい。すなわち、熱緩和工程において熱緩和処理を複数回行う場合、熱緩和処理と熱緩和処理の間で親水化処理を行ってもよい。 The hydrophilization treatment may be carried out after the stretching step and before the heat-relaxing step, after the stretching step and the heat-relaxing step, or during the heat-relaxing step. In other words, if the heat-relaxing step involves multiple heat-relaxing treatments, the hydrophilization treatment may be carried out between the heat-relaxing treatments.
＜中空糸膜エレメント＞
本実施形態の中空糸膜エレメントは、複数本の多孔質中空糸膜と、前記複数の多孔質中空糸膜の両端に接続された集水管とを有する。
図１は本実施形態の中空糸膜エレメントの一態様を示す平面図である。
本態様の中空糸膜エレメントは、複数本の多孔質中空糸膜１が一方向に引き揃えられたシート物２と、シート状物２の多孔質中空糸膜１の長さ方向の両端部にそれぞれ設けられた集水管３、４を備える。
多孔質中空糸膜１の長さ方向の両端は開口しており、多孔質中空糸膜１と集水管３、４とは連通している。具体的に、集水管３、４の管壁には、集水管３、４の長さ方向に沿う直線状のスリット（図示略）が設けられている。このスリットにシート状物２の端部が挿入され、多孔質中空糸膜１の開口を保った状態で、樹脂硬化物等のポッティング材で、シート状物２の端部と集水管３（４）とが固定されている。
本態様において、多孔質中空糸膜１の外部から内部へ通過した濾過水は、集水管３、４を通って中空糸膜エレメントの外部へ排出されるようになっている。
<Hollow fiber membrane element>
The hollow fiber membrane element of this embodiment has a plurality of porous hollow fiber membranes and water collection pipes connected to both ends of the plurality of porous hollow fiber membranes.
FIG. 1 is a plan view showing one embodiment of the hollow fiber membrane element of the present embodiment.
The hollow fiber membrane element of this embodiment comprises a
Both ends in the longitudinal direction of the porous hollow fiber membrane 1 are open, and the porous hollow fiber membrane 1 communicates with the
In this embodiment, the filtrate that has passed from the outside to the inside of the porous hollow fiber membrane 1 passes through the
本態様の中空糸膜エレメントは、水処理装置の構成部材として好適に用いられる。例えば、生活排水や工場排水等の浄化処理に用いられる水処理装置の構成部材として好適である。
本態様の中空糸膜エレメントは、複数の中空糸膜エレメントを一体的に取り扱えるように構成した中空糸膜モジュールの形態で用いることが好ましい。
例えば、中空糸膜モジュールは、複数の中空糸膜エレメントと、前記複数の中空糸膜エレメントを一体的に支持する支持部材を備える。支持部材は、各中空糸膜エレメントの集水管（枝管）と連通する集水管（幹管）を兼ねてもよい。
中空糸膜モジュールの構成、及び水処理装置の構成は、公知の構成を用いることができる。
The hollow fiber membrane element of this embodiment is suitable for use as a component of a water treatment device, for example, a component of a water treatment device used for purifying domestic wastewater, industrial wastewater, and the like.
The hollow fiber membrane element of this embodiment is preferably used in the form of a hollow fiber membrane module configured so that a plurality of hollow fiber membrane elements can be handled as an integrated unit.
For example, the hollow fiber membrane module includes a plurality of hollow fiber membrane elements and a support member that integrally supports the plurality of hollow fiber membrane elements. The support member may also serve as a water collection pipe (main pipe) that communicates with the water collection pipes (branch pipes) of each hollow fiber membrane element.
The hollow fiber membrane module and the water treatment device may have a known configuration.
本実施形態の中空糸膜エレメントを構成する多孔質中空糸膜は、水に浸漬した後に乾燥した際の収縮率が小さいため、洗浄に伴う性能低下や糸切れが生じ難く、中空糸膜エレメントの長寿命化、交換回数の低減を図ることができる。 The porous hollow fiber membrane that constitutes the hollow fiber membrane element of this embodiment has a small shrinkage rate when dried after immersed in water, so performance degradation and fiber breakage due to cleaning are unlikely to occur, and the hollow fiber membrane element can have a longer life and require fewer replacements.
以下に実施例を用いて本発明をさらに詳しく説明するが、本発明はこれら実施例に限定されるものではない。 The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.
（参考例）
ポリエチレン（密度０．９６５ｇ／ｃｍ３、ＭＦＲ：０．７ｇ／１０分、Ｔｇ：－１２５℃、ビカット軟化点１２８℃）を原料とし、中空糸膜製造用ノズルを用いて溶融紡糸し、冷却固化して、内径６０９μｍ、膜厚１６１μｍの中空糸を得た。
中空糸をボビンに巻いた状態で、１１５℃、１６時間の条件でアニール処理した。
アニール処理した中空糸を、室温で、延伸倍率が１．８倍になるように冷延伸した後、延伸温度１１４℃で熱延伸した後、親水化処理して多孔質中空糸膜を得た。熱延伸の延伸倍率は、冷延伸を含めた総延伸倍率が６．６倍となるように設定した。
得られた多孔質中空糸膜の外径、内径、平均孔径を表１に示す。また、得られた多孔質中空糸膜について、上記の方法で収縮率を測定した。結果を表１に示す（以下、同様）。
(Reference example)
Polyethylene (density 0.965 g/cm 3 , MFR: 0.7 g/10 min, Tg: -125°C, Vicat softening point 128°C) was used as the raw material, which was melt spun using a nozzle for producing hollow fiber membranes and then cooled and solidified to obtain hollow fibers with an inner diameter of 609 μm and a membrane thickness of 161 μm.
The hollow fiber was wound on a bobbin and then annealed at 115° C. for 16 hours.
The annealed hollow fiber was cold-stretched at room temperature to a stretch ratio of 1.8, then hot-stretched at a stretching temperature of 114° C., and then hydrophilized to obtain a porous hollow fiber membrane. The stretch ratio of the hot stretching was set so that the total stretch ratio including the cold stretching was 6.6.
The outer diameter, inner diameter, and average pore size of the obtained porous hollow fiber membrane are shown in Table 1. The shrinkage rate of the obtained porous hollow fiber membrane was measured by the above-mentioned method. The results are shown in Table 1 (hereinafter the same).
（例１）
参考例１と同様にして中空糸を製造し、アニール処理し、冷延伸し、熱延伸し、親水化処理した。得られた中空糸膜に対して、熱緩和温度１１８℃、緩和率０％の条件で熱緩和処理をして多孔質中空糸膜を得た。
(Example 1)
A hollow fiber was produced, annealed, cold-stretched, hot-stretched, and hydrophilized in the same manner as in Reference Example 1. The resulting hollow fiber membrane was subjected to a heat-relaxation treatment under conditions of a heat-relaxation temperature of 118° C. and a relaxation rate of 0%, to obtain a porous hollow fiber membrane.
（例２）
例１において、熱緩和処理の緩和率を１５％に変更したほかは、例１と同様にして多孔質中空糸膜を得た。
(Example 2)
A porous hollow fiber membrane was obtained in the same manner as in Example 1, except that the relaxation rate of the heat-relaxing treatment was changed to 15%.
（例３）
参考例１と同様にして中空糸を製造し、アニール処理し、冷延伸し、熱延伸した。得られた中空糸膜に対して、熱緩和温度１１８℃、緩和率２０％の条件で１回目の熱緩和処理をした後、参考例１と同様にして親水化処理した。親水化処理後の中空糸膜に対して、熱緩和温度９０℃、緩和率０％の条件で２回目の熱緩和処理をして多孔質中空糸膜を得た。
(Example 3)
A hollow fiber was produced, annealed, cold stretched, and hot stretched in the same manner as in Reference Example 1. The obtained hollow fiber membrane was subjected to a first heat-relaxing treatment under conditions of a heat-relaxing temperature of 118° C. and a relaxation rate of 20%, and then to a hydrophilization treatment in the same manner as in Reference Example 1. The hollow fiber membrane after the hydrophilization treatment was subjected to a second heat-relaxing treatment under conditions of a heat-relaxing temperature of 90° C. and a relaxation rate of 0%, to obtain a porous hollow fiber membrane.
（例４）
例３において、２回目の熱緩和処理の熱緩和温度を１１０℃に変更したほかは、例３と同様にして多孔質中空糸膜を得た。
(Example 4)
A porous hollow fiber membrane was obtained in the same manner as in Example 3, except that the heat-relaxing temperature in the second heat-relaxing treatment was changed to 110°C.
（例５）
例４において、２回目の熱緩和処理の緩和率を３％に変更したほかは、例４と同様にして多孔質中空糸膜を得た。
(Example 5)
A porous hollow fiber membrane was obtained in the same manner as in Example 4, except that the relaxation rate in the second heat-relaxing treatment was changed to 3%.
表１に示されるように、熱緩和処理の条件を変えることによって多孔質中空糸膜の収縮率を３％以下に調整できた。 As shown in Table 1, the shrinkage rate of the porous hollow fiber membrane could be adjusted to 3% or less by changing the conditions of the heat relaxation treatment.
１ 多孔質中空糸膜
２ シート状物
３、４ 集水管
1 Porous
Claims (2)
前記中空糸を延伸して中空糸膜を得る延伸工程と、
前記延伸工程の後、前記中空糸膜を熱緩和処理する１回目の熱緩和工程と、
前記１回目の熱緩和工程の後、前記中空糸膜を親水化処理する親水化工程と、
前記親水化工程の後、前記中空糸膜を熱緩和処理する２回目の熱緩和工程とを有する、下記の測定方法で得られる収縮率が３％以下である多孔質中空糸膜の製造方法であって、
前記１回目の熱緩和工程における緩和率は、前記２回目の熱緩和工程における緩和率より高いことを特徴とする、多孔質中空糸膜の製造方法。
測定方法：長さ４００ｍｍの多孔質中空糸膜を、エタノールに１０分間浸漬した後、純水に１０分間浸漬し、６０℃の雰囲気中で３０分間乾燥した後、室温で５分間冷却する浸漬処理を行い、処理後の前記多孔質中空糸膜の長さＬ１（単位：ｍｍ）を測定し、下記式（Ｉ）により収縮率（単位：％）を算出する。
収縮率＝（４００－Ｌ１）／４００×１００ ・・・（Ｉ） A spinning step of melt spinning a raw material containing a polyolefin resin to obtain a hollow fiber;
a stretching step of stretching the hollow fiber to obtain a hollow fiber membrane;
a first heat-relaxing step in which the hollow fiber membrane is heat-relaxed after the stretching step;
a hydrophilization step of subjecting the hollow fiber membrane to a hydrophilic treatment after the first heat relaxation step;
A method for producing a porous hollow fiber membrane having a shrinkage rate of 3% or less as measured by the following measurement method , the method comprising : a second heat-relaxing step of heat-relaxing the hollow fiber membrane after the hydrophilization step ,
A method for producing a porous hollow fiber membrane, wherein a relaxation rate in the first heat-relaxing step is higher than a relaxation rate in the second heat-relaxing step.
Measurement method: A porous hollow fiber membrane having a length of 400 mm is immersed in ethanol for 10 minutes, then immersed in pure water for 10 minutes, dried in an atmosphere at 60°C for 30 minutes, and then cooled at room temperature for 5 minutes. The length L1 (unit: mm) of the porous hollow fiber membrane after the treatment is measured, and the shrinkage rate (unit: %) is calculated by the following formula (I).
Shrinkage rate = (400 - L1) / 400 x 100 ... (I)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2020073459A JP7562983B2 (en) | 2020-04-16 | 2020-04-16 | Method for producing porous hollow fiber membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2020073459A JP7562983B2 (en) | 2020-04-16 | 2020-04-16 | Method for producing porous hollow fiber membrane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2021169065A JP2021169065A (en) | 2021-10-28 |
| JP7562983B2 true JP7562983B2 (en) | 2024-10-08 |
Family
ID=78149803
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2020073459A Active JP7562983B2 (en) | 2020-04-16 | 2020-04-16 | Method for producing porous hollow fiber membrane |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7562983B2 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000288357A (en) | 1999-04-01 | 2000-10-17 | Mitsubishi Rayon Co Ltd | Method for manufacturing hollow fiber membrane module, hollow fiber membrane module, and hollow fiber membrane module unit using the same |
| WO2018092342A1 (en) | 2016-11-15 | 2018-05-24 | 住友電気工業株式会社 | Filtration module and filtration device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0691945B2 (en) * | 1986-03-25 | 1994-11-16 | 旭メデイカル株式会社 | Polyethylene porous hollow fiber |
| JPS6451101A (en) * | 1987-08-19 | 1989-02-27 | Mitsubishi Rayon Co | Heat resistant polyethylene porous membrane and its preparation |
-
2020
- 2020-04-16 JP JP2020073459A patent/JP7562983B2/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000288357A (en) | 1999-04-01 | 2000-10-17 | Mitsubishi Rayon Co Ltd | Method for manufacturing hollow fiber membrane module, hollow fiber membrane module, and hollow fiber membrane module unit using the same |
| WO2018092342A1 (en) | 2016-11-15 | 2018-05-24 | 住友電気工業株式会社 | Filtration module and filtration device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2021169065A (en) | 2021-10-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104117289B (en) | One kind enhancing composite support hollow-fibre membrane and preparation method thereof | |
| CN101316646B (en) | A braid-reinforced composite hollow fiber membrane | |
| KR101077954B1 (en) | Polysulfone hollow fiber membrane with excellent strength and water permeability and its manufacturing method | |
| CN105722585A (en) | Porous hollow fiber membrane and method for manufacturing same | |
| KR101589746B1 (en) | Hollow fiber membrane and method for manufacturing the same | |
| EP3257572A1 (en) | Bundle of hollow fiber membranes and manufacturing method therefor | |
| US20150283517A1 (en) | Hollow porous membrane | |
| CN105636676B (en) | hollow porous membrane | |
| KR20160081612A (en) | PVDF porous hollow fiber membrane and the preparing method thereof | |
| JP7562983B2 (en) | Method for producing porous hollow fiber membrane | |
| KR101206656B1 (en) | Manufacturing Method for Composite Hollow Fiber Membrane using a Tubular braid and Composite Hollow Fiber Membrane thereby | |
| JP6638276B2 (en) | Method for producing porous hollow fiber membrane | |
| JPH06246140A (en) | Method for producing hollow fiber heterogeneous membrane | |
| JP6209983B2 (en) | Polyethylene hollow fiber membrane and method for producing polyethylene hollow fiber membrane | |
| JPH0780263A (en) | Method for producing polypropylene porous hollow fiber membrane | |
| KR100977397B1 (en) | Symmetric porous hollow fiber membrane supported by annular knitted fabric and its manufacturing method | |
| US10471395B2 (en) | Hollow fiber membrane and method of preparing the same | |
| KR101178653B1 (en) | Tubular braid and Composite Hollow Fiber Membrane Using The Same | |
| JP2010137196A (en) | Method for manufacturing porous hollow-fiber membrane | |
| JPH028047B2 (en) | ||
| JP2018130724A (en) | Manufacturing method of water treatment membrane element | |
| JPH08252441A (en) | Polypropylene hollow fiber membrane and method for producing the same | |
| KR101596037B1 (en) | Hollow fiber membrane and method for manufacturing the same | |
| JP3250808B2 (en) | Polysulfone porous membrane and method for producing the same | |
| KR101226400B1 (en) | Tubular braid and Composite Hollow Fiber Membrane using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20221107 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20230712 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230905 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20231031 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20231222 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20240305 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20240527 |
|
| A911 | Transfer to examiner for re-examination before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20240603 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20240827 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20240909 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7562983 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |